Radar signal processing method, radar signal processing device, radio signal processing method, integrated circuit, radio device, and device

Abstract

The radar signal processing method includes: after an echo signal is mixed based on a local oscillator signal, and digital signal processing is performed to obtain a signal to be processed, the signal to be processed is subtracted based on a datum difference frequency signal to obtain a target signal, and a travelling speed of a target relative to a radar and/or a distance of the target relative to the radar is determined according to the target signal. Since the datum differential frequency signal is a signal obtained by mixing a leakage signal based on the local oscillator signal and performing the digital signal processing in a target free environment. Therefore, subtracting the signal to be processed based on the datum differential frequency signal can effectively reduce the content of the leakage signal in the signal to be processed, thereby improving the accuracy of the measurement results.

What is claimed is: 
     
         1 . A radar signal processing method, comprising:
 transmitting, by a transmitting antenna of a radar, radio signals to a target, the radio signals being based on a local oscillator signal;   receiving, by a receiving antenna of the radar, echo signals from the target reflecting the radio signals;   mixing the echo signal with the local oscillator signal to obtain a first mixed signal, and performing digital signal processing on the first mixed signal to obtain a signal to be processed;   subtracting a datum difference frequency signal from the signal to be processed to obtain a target signal; and,   determining a travelling speed of the target relative to the radar and/or a distance of the target relative to the radar according to the target signal;   wherein the datum difference frequency signal is obtained by mixing a leakage signal with the local oscillator signal to obtain a second mixed signal and performing digital signal processing on the second mixed signal, the leakage signal corresponding to a signal received by the receiving antenna of the radar in a target free environment, and wherein the datum difference frequency signal is stored before being used to obtain the target signal.   
     
     
         2 . The radar signal processing method according to  claim 1 , wherein the datum difference frequency signal is a time domain signal;
 subtracting the datum difference frequency signal from the signal to be processed to obtain the target signal comprises:   calculating an amplitude difference between the signal to be processed and the datum difference frequency signal at a plurality of time points to obtain a plurality of first subtracted data;   taking each of the plurality of first subtracted data as signal data of the signal to be processed at a corresponding time, and taking the signal to be processed that has been subtracted as the target signal.   
     
     
         3 . The radar signal processing method according to  claim 2 , wherein determining the travelling speed of the target relative to the radar and/or the distance of the target relative to the radar according to the target signal comprises:
 performing two-dimensional fast Fourier transform (2D FFT) on the target signal to obtain a first transformation result;   determining the travelling speed of the target relative to the radar and/or the distance of the target relative to the radar according to the first transformation result.   
     
     
         4 . The radar signal processing method according to  claim 1 , wherein in response to the datum difference frequency signal being characterized by transformation result obtained after range FFT is performed on time domain waveform of the datum difference frequency signal,
 subtracting the datum difference frequency signal from the signal to be processed to obtain the target signal comprises:   performing range FFT on the signal to be processed to obtain a first preprocessed signal;   subtracting the datum frequency difference signal from the first preprocessed signal at a plurality of same frequency points to obtain complex difference serving as a plurality of second subtracted data;   taking each of the plurality of second subtracted data as signal data of the first preprocessed signal at a corresponding frequency point, and taking the first preprocessed signal that has been subtracted as the target signal.   
     
     
         5 . The radar signal processing method according to  claim 4 , wherein determining the travelling speed of the target relative to the radar and/or the distance of the target relative to the radar according to the target signal comprises:
 performing doppler FFT on the target signal to obtain a second transformation result;   determining the travelling speed of the target relative to the radar and/or the distance of the target relative to the radar according to the second transformation result.   
     
     
         6 . The radar signal processing method according to  claim 1 , wherein in response to the datum difference frequency signal being characterized by transformation result obtained after 2D FFT is performed on time domain waveform of the datum difference frequency signal,
 subtracting the datum difference frequency signal from the signal to be processed to obtain the target signal comprises:   performing 2D FFT on the signal to be processed to obtain a second preprocessed signal;   subtracting the datum frequency difference signal from the second preprocessed signal at a plurality of same frequency points to obtain complex difference serving as a plurality of third subtracted data;   taking each of the plurality of third subtracted data as signal data of the second preprocessed signal at a corresponding frequency point, and taking the second preprocessed signal that has been subtracted as the target signal.   
     
     
         7 . The radar signal processing method according to  claim 1 , further comprising:
 determining an azimuth of the target according the travelling speed of the target relative to the radar and/or the distance of the target relative to the radar.   
     
     
         8 . A radar signal processing device, comprising:
 an obtaining unit, configured to mix an echo signal from a target with a local oscillator signal to obtain a first mixed signal, and performing digital signal processing on the first mixed signal to obtain a signal to be processed;   a subtracting unit, configured to subtract a datum difference frequency signal from the signal to be processed to obtain a target signal; and   a first determining unit, configured to determine a travelling speed of the target relative to a radar and/or a distance of the target relative to the radar according to the target signal;   wherein the datum difference frequency signal is a signal obtained by mixing a leakage signal with the local oscillator signal to obtain a second mixed signal and performing the digital signal processing on the second mixed signal, the leakage signal corresponding to a signal received by a receiving antenna of a radar in a target free environment, and wherein the datum difference frequency signal is stored before being used to obtain the target signal.   
     
     
         9 . A radio signal processing method, comprising:
 receiving a first received signal fed back from a target at a receiving antenna of a radar,   performing a preset digital signal processing operation on the first received signal to obtain a signal to be processed; and   subtracting a reference difference frequency signal from the signal to be processed to obtain a target signal;   wherein the reference difference frequency signal is a signal obtained by performing the preset digital signal processing operation on a second received signal, the second received signal corresponding to a signal received by the receiving antenna in a preset specific environment, and wherein the reference difference frequency signal is stored before being used to obtain the target signal.   
     
     
         10 . The radio signal processing method according to  claim 9 , wherein the first received signal is an echo signal of the target, and the radio signal processing method comprises:
 mixing the echo signal with a local oscillator signal to obtain a first mixed signal, and performing digital signal processing on the first mixed signal to obtain the signal to be processed;   subtracting the reference difference frequency signal from the signal to be processed to obtain the target signal; and,   determining information of the target based on the target signal;   wherein the reference difference frequency signal is a signal obtained by mixing the second received signal with the local oscillator signal to obtain a second mixed signal and performing the preset digital signal processing on the second mixed signal.   
     
     
         11 . The radio signal processing method according to  claim 9 , wherein the preset digital signal processing operation comprises an analog-to-digital conversion operation, a sampling operation, a range FFT operation, a doppler FFT operation, and a CFAR operation performed sequentially;
 wherein between any two operations of the sampling operation, the range FFT operation, the doppler FFT operation, and the CFAR operation, the target signal is obtained by subtracting the reference difference frequency signal from the signal to be processed.   
     
     
         12 . The radio signal processing method according to  claim 10 , wherein the information of the target comprises at least one of distance, velocity, angle, size, shape, surface roughness, dielectric property, and motion path. 
     
     
         13 . The radio signal processing method according to  claim 11 , wherein the information of the target comprises at least one of distance, velocity, angle, size, shape, surface roughness, dielectric property, and motion path. 
     
     
         14 . The radio signal processing method according to  claim 9 , wherein the preset specific environment is a target free environment or an environment with specific interference. 
     
     
         15 . An integrated circuit, comprising:
 a storage module, configured to store a datum difference frequency signal in advance;   a digital signal processing module, configured to call the datum difference frequency signal from the storage module and to perform the radar signal processing method according to  claim 1  to eliminate signal leakage interference.   
     
     
         16 . A radio device, comprising:
 a carrier;   an integrated circuit, wherein the integrated circuit is the integrated circuit according to  claim 15 , and the integrated circuit is arranged on the carrier; and   an antenna, wherein the antenna is arranged on the carrier, or the antenna is integrated with the integrated circuit to form an integrated device, and the integrated device is arranged on the carrier;   the integrated circuit is connected to the antenna, to transmit and receive radio signals.   
     
     
         17 . A device, comprising:
 a device main body; and   a radio device, wherein the radio device is the radio device according to  claim 16 , and the radio device is arranged on the device main body;   wherein the radio device is configured to perform target detection and/or communication.   
     
     
         18 . An integrated circuit, comprising:
 a storage module, configured to store a reference difference frequency signal in advance;   a digital signal processing module, configured to call the reference difference frequency signal from the storage module and to perform the radar signal processing method according to  claim 9  to eliminate specific interference signals in the preset specific environment.   
     
     
         19 . A radio device, comprising:
 a carrier;   an integrated circuit, wherein the integrated circuit is the integrated circuit according to  claim 18 , and the integrated circuit is arranged on the carrier; and   an antenna, wherein the antenna is arranged on the carrier, or the antenna is integrated with the integrated circuit to form an integrated device, and the integrated device is arranged on the carrier;   the integrated circuit is connected to the antenna, to transmit and receive radio signals.